Adaptive synchronization of orientation-specific cortical oscillations for therapeutic neuromodulation

Abstract

A method for modulating the electrical synchronization of the cerebral cortex within safe limits by computing the orientation of the applied currents with respect to the orientation of the cortical surface and thus cortical columns. Ongoing electroencephalographic monitoring, including the synchronization of induced with stimulating currents, may confirm the precision and safety of the applied currents.

1 . A method of cortical neuromodulation comprising the steps of:
 delivering transcranial electrical stimulation to a targeted subset of cortical columns oriented perpendicularly to the scalp,   measuring and modeling the electrical field distribution in relation to the columnar orientation of the cortex,   synchronizing the induced electrical field with endogenous oscillatory activity in the functional (e.g., gamma or spindle) frequency range,   and computing the degree of synchronization as a quantitative metric of effective modulation of excitatory-inhibitory (E-I) balance in the stimulated cortical networks.   
     
     
         2 . The method of  claim 1  wherein said synchronization targets gamma oscillations in the range of 30-80 Hz for therapeutic modulation in Alzheimer's Disease. 
     
     
         3 . The method of  claim 1  wherein said synchronization targets sleep spindle activity in the 9-16 Hz range to enhance deep sleep-associated neural plasticity. 
     
     
         4 . A system for neuromodulation comprising:
 a high-resolution EEG source localization system for measuring columnar cortical orientation,   an electrical stimulation unit capable of delivering time-locked waveforms at functional (e.g., gamma or spindle) frequencies,   a feedback system that quantifies synchronization between induced and endogenous oscillations, and   a control unit that modulates stimulation amplitude, phase, and frequency to maintain synchronization within a safe E-I balance.   
     
     
         5 . The system of  claim 4  wherein synchronization metrics are used to optimize stimulation in real time and avoid both under-synchronization and over-synchronization, 
     
     
         6 . The system of  claim 4  wherein the induced electrical field is shaped to align with the anatomical orientation of targeted cortical columns using inverse modeling of scalp potentials and brain conductivity profiles. 
     
     
         7 . The method of  claim 1  further comprising:
 continuous monitoring of electrical and neural activity to detect subclinical epileptiform discharges, 
 dynamic adjustment of stimulation parameters to prevent seizure onset, 
 and maintaining stimulation within a critical regime of neural synchrony, defined as enhanced coherence without super-critical excitatory entrainment. 
 
     
     
         8 . A method for safely applying excitatory cortical stimulation in Alzheimer's Disease patients comprising:
 determining an individualized excitatory-inhibitory balance threshold for each patient,   measuring the deviation from this threshold during stimulation,   and automatically adjusting stimulation parameters to avoid exceeding the seizure-critical limit.   
     
     
         9 . The system of  claim 4  wherein neural synchrony is computed using real-time EEG phase-locking value (PLV) or coherence metrics, and stimulation is halted or reduced if the synchrony exceeds a predefined safety envelope. 
     
     
         10 . The method of  claim 1  wherein the induced oscillatory stimulation is constrained to cortical regions with low susceptibility to seizure propagation, as determined by individual neurophysiological and anatomical markers. 
     
     
         11 . The method of  claim 1  wherein synchronization to beneficial oscillations (gamma during waking, spindle during sleep) is achieved using the same stimulation hardware, adapted in frequency and waveform phase-locking profiles, with safety constraints enabled via the E-I balance quantification algorithm. 
     
     
         12 . A non-transitory computer-readable medium storing instructions that, when executed, control the modulation of cortical electrical stimulation based on individualized modeling of cortical column orientation, E-I balance, oscillatory phase-locking, and seizure risk thresholds.